Long dishId = shoppingCart.getDishId(); LambdaQueryWrapper<ShoppingCart> queryWrapper=new LambdaQueryWrapper<>(); queryWrapper.eq(ShoppingCart::getUserId,id); if (dishId!=null){ queryWrapper.eq(ShoppingCart::getDishId,dishId); }else { queryWrapper.eq(ShoppingCart::getSetmealId,shoppingCart.getSetmealId()); } ShoppingCart cartserviceOne = shoppingCartservice.getOne(queryWrapper); if (cartserviceOne!=null){ Integer number = cartserviceOne.getNumber(); cartserviceOne.setNumber(number+1); shoppingCartservice.updateById(cartserviceOne); }else { shoppingCart.setNumber(1); shoppingCartservice.save(shoppingCart); cartserviceOne=shoppingCart; }

jquery.shoppingcart:使用本地存储的简单购物车jQuery插件

script src =" /path/to/jquery.shoppingcart.js " > </ script > 浏览器要求用法新增项目： $ . shoppingcart ( 'add' , { 'id' : 123 , 'image' : 'path/to/image.png' , 'name' : '...

ShoppingCart.zip

"ShoppingCart.zip"可能包含一个实现此类功能的软件项目或代码库。在这个压缩包中，"ShoppingCart"可能是主程序文件或者目录，包含了整个购物车系统的源代码、配置文件、数据库脚本和其他相关资源。购物车系统的...

shoppingcart.jsp

import React, { useState, PropsWithChildren } from "react" interface AppStateValue { username: string shoppingCart: { id: number; name: string }[] } const defaultContextValue: AppStateValue = { username: "JOKER", shoppingCart: [], } export const appContext = React.createContext(defaultContextValue) export const appSetStateContext = React.createContext< React.Dispatch<React.SetStateAction<AppStateValue>> | undefined >(undefined) export const DemoStateProvider: React.FC> = props => { const [state, setState] = useState(defaultContextValue) return ( <appContext.Provider value={state}> <appSetStateContext.Provider value={setState}> {props.children} </appSetStateContext.Provider> </appContext.Provider> ) } import React, { useContext } from "react" import styles from "./Robot.module.css" import { appContext, appSetStateContext } from "../demoState" interface RobotProps { id: number name: string email: string } const Robot: React.FC<RobotProps> = ({ id, name, email }) => { const value = useContext(appContext) const setState = useContext(appSetStateContext) const addToCart = () => { console.log(setState, "@@") if (setState) { // 思考: 同学们可以想一想如何化简这里的代码 setState(state => { console.log(state, "??") return { ...state, shoppingCart: [...state.shoppingCart, { id, name }], } }) } } return ( {name} {email} 作者：{value.username} <button onClick={addToCart}>加入购物车</button> ) } export default Robot console.log(setState, "@@") 为什么这里式undefined

这里的setState是在函数组件中使用useContext从appSetStateContext上下文中获取的。如果在组件树中没有提供appSetStateContext的上下文，那么setState就会是undefined。通常情况下，这种情况会发生在...

queryWrapper.eq(ShoppingCart::getDishId,dishId); //这里必须要加两个条件，否则会出现用户互相修改对方与自己购物车中相同套餐或者是菜品的数量 queryWrapper.eq(ShoppingCart::getUserId,BaseContext.getCurrentId()); ShoppingCart cart1 = shoppingCartService.getOne(queryWrapper);

1. queryWrapper.eq(ShoppingCart::getDishId, dishId)：该条件用于匹配购物车中的dishId字段与指定的dishId值相等的记录。 2. queryWrapper.eq(ShoppingCart::getUserId, BaseContext.getCurrentId())：该...

BigDecimal totalAmount = BigDecimal.valueOf(0); for (ShoppingCart shoppingCart : shoppingCarts) { BigDecimal amount = shoppingCart.getAmount(); Integer number = shoppingCart.getNumber(); totalAmount += amount * number; }

BigDecimal amount = shoppingCart.getAmount(); Integer number = shoppingCart.getNumber(); totalAmount = totalAmount.add(amount.multiply(BigDecimal.valueOf(number))); } 这里使用了 multiply() ...

请帮我测试下列代码是否能正常运行，并告知我下列代码的作用：import java.util.ArrayList; import java.util.List; class Product { private String name; private double price; public Product(String name, double price) { this.name = name; this.price = price; } // Getters and setters // Other methods } class ShoppingCart { private List products; public ShoppingCart() { this.products = new ArrayList<>(); } public void addProduct(Product product) { products.add(product); } public void removeProduct(Product product) { products.remove(product); } public double calculateTotalPrice() { double totalPrice = 0; for (Product product : products) { totalPrice += product.getPrice(); } return totalPrice; } // Other methods } class Main { public static void main(String[] args) { // Create some products Product product1 = new Product("Product 1", 10.99); Product product2 = new Product("Product 2", 19.99); Product product3 = new Product("Product 3", 5.99); // Create a shopping cart ShoppingCart shoppingCart = new ShoppingCart(); // Add products to the shopping cart shoppingCart.addProduct(product1); shoppingCart.addProduct(product2); shoppingCart.addProduct(product3); // Remove a product from the shopping cart shoppingCart.removeProduct(product2); // Calculate the total price of the products in the shopping cart double totalPrice = shoppingCart.calculateTotalPrice(); System.out.println("Total price: $" + totalPrice); } }

它定义了三个类：Product、ShoppingCart和Main。 Product类表示一个产品，具有两个私有属性：name表示产品的名称，price表示产品的价格。它还有一个构造函数用于初始化这些属性。 ShoppingCart类...

<template> <el-menu :default-active="activeIndex" class="el-menu-demo" mode="horizontal" @select="handleSelect" > <el-menu-item index="index">主页</el-menu-item> <el-menu-item index="shoppingCart">购物车</el-menu-item> <el-menu-item index="me">用户</el-menu-item> </el-menu> <router-view></router-view> </template> <script> import "@element-plus/icons-vue"; export default { name: "App", components: { }, data(){ return { } }, methods:{ //路由切换 handleSelect(key){ this.$router.push(key) } } }; </script> <style > html, body, #app { height: 100%; } body { height: 100%; background-color: #f1f2f6; } </style>

1. <template> 标签：包含了组件的模板内容，其中包括一个菜单和一个路由视图。 2. <el-menu> 标签：是一个 Element Plus 的菜单组件，用于展示导航菜单。其中包括了三个 <el-menu-item> 标签，分别代表了...

<jsp:useBean id="cart" scope="session" class="model.ShoppingCart"></jsp:useBean>

在这个例子中，<jsp:useBean>标签声明了一个名为“cart”的JavaBean对象，类名为model.ShoppingCart，作用域为session级别。这意味着，该JavaBean对象可以在当前会话中的其他JSP页面中被共享和访问。需要注意的是...

List<ShoppingCart> shoppingCartList = orderDetailList.stream().map(x -> { ShoppingCart shoppingCart = new ShoppingCart(); // 将原订单详情里面的菜品信息重新复制到购物车对象中 BeanUtils.copyProperties(x, shoppingCart, "id"); shoppingCart.setUserId(userId); shoppingCart.setCreateTime(LocalDateTime.now()); return shoppingCart; }).collect(Collectors.toList());

这段代码使用了Java 8的Stream API，将一个订单详情列表转换成了一个购物车列表。具体来说，它使用map操作将每个订单详情对象转换成一个购物车对象，然后使用BeanUtils.copyProperties方法将原订单详情里面的菜品...

class Order{ Scanner scan=new Scanner(System.in); public int Random() { Random rd=new Random(); int[] arr=rd.ints(1).toArray(); for(int i=0;i<arr.length;i++){ if(arr[i]<0) System.out.println(arr[i]-1); } return rd.nextInt(); } public double totalPrice() { return shoppingCart.shoppinggoods.stream().mapToDouble(item -> item.getPrice() item.getQuantity()).sum(); } // public double totalPrice() { // double sum = 0; // for (int i = 0; i < shoppingCart.shoppinggoods.size(); i++) { // sum += shoppingCart.shoppinggoods.get(i).getQuantity() * shoppingCart.shoppinggoods.get(i).getPrice(); // } // return sum; // } public void print() { System.out.println("请输入收货地址："); String address=scan.nextLine(); System.out.println("id"+"\t"+"名称"+"\t"+"类型"+"\t"+"价格"+"\t"+"数量"); System.out.println(shoppingCart.shoppinggoods); System.out.println("共计："+totalPrice()); System.out.println("订单编号："+Random()); new User().print(); System.out.println("收货地址："+address); } }怎么添加多态

return shoppingCart.shoppinggoods.stream().mapToDouble(item -> item.getPrice() * item.getQuantity()).sum(); } public void print() { System.out.println("请输入收货地址："); String address=scan....

JSTL流程控制：<c:choose>实例解析

本资源聚焦于流程控制部分，具体是JSTL中的 <c:choose>、<c:when> 和 <c:otherwise> 范例。 <c:choose>标签用于根据条件选择执行其中的一个或多个子标签。当提供的条件表达式（如${condition1} 或 ${...

EL语言与JSTL标签库：<fmt:setLocale>解析

"<fmt:setLocale>标记-EL表达式与JSTL标签库." EL（Expression Language）是Java服务器页面（JSP）中的一种强大而简洁的表达式语言，用于访问和操作存储在各种作用域（如page, request, session, application）中的...

如何调用函数class Item: def init(self, name, price): self.name = name self.price = price def get_name(self): return self.name def get_price(self): return self.price class ShoppingCart: def init(self): self.items = {} def add_item(self, item, quantity): if item in self.items: self.items[item] += quantity else: self.items[item] = quantity def remove_item(self, item, quantity): if item in self.items: if self.items[item] <= quantity: del self.items[item] else: self.items[item] -= quantity def get_total(self): total = 0 for item, quantity in self.items.items(): total += item.get_price() * quantity return total def get_item_count(self): count = 0 for quantity in self.items.values(): count += quantity return count def get_items(self): return self.items

shopping_cart = ShoppingCart() shopping_cart.add_item(item, 3) shopping_cart.remove_item(item, 1) total = shopping_cart.get_total() count = shopping_cart.get_item_count() items = shopping_cart.get_...

编写函数并调用class ShoppingCart: def init(self): self.items = {} def add_item(self, item, quantity): if item in self.items: self.items[item] += quantity else: self.items[item] = quantity def remove_item(self, item, quantity): if item in self.items: if self.items[item] <= quantity: del self.items[item] else: self.items[item] -= quantity def get_total(self): total = 0 for item, quantity in self.items.items(): total += item.get_price() * quantity return total def get_item_count(self): count = 0 for quantity in self.items.values(): count += quantity return count def get_items(self): return self.items

if self.items[item] <= quantity: del self.items[item] else: self.items[item] -= quantity def get_total(self): total = 0 for item, quantity in self.items.items(): total += item.get_price() * ...

用java帮我写public class ShoppingCart { private int itemCount; // 购物车中商品数量 private double totalPrice; // 购物车中商品总价钱 private Map<String, Integer> cartItems; // 购物车中商品信息 public ShoppingCart() { itemCount = 0; totalPrice = 0.0; cartItems = new HashMap<String, Integer>(); } // 添加商品到购物车 public void addItem(String productId, int quantity, double price) { if (!cartItems.containsKey(productId)) { cartItems.put(productId, quantity); } else { int qty = cartItems.get(productId); qty += quantity; cartItems.put(productId, qty); } itemCount += quantity; totalPrice += price * quantity; } // 更新购物车中商品数量 public void update(String productId, int quantity, double price) { if (cartItems.containsKey(productId)) { int qty = cartItems.get(productId); itemCount -= qty; totalPrice -= qty * price; cartItems.put(productId, quantity); itemCount += quantity; totalPrice += quantity * price; } } // 删除购物车中的商品 public void removeItem(String productId, double price) { if (cartItems.containsKey(productId)) { int qty = cartItems.get(productId); itemCount -= qty; totalPrice -= qty * price; cartItems.remove(productId); } } // 清空购物车 public void clear() { cartItems.clear(); itemCount = 0; totalPrice = 0.0; } // 获取购物车中商品数量 public int getItemCount() { return itemCount; } // 获取购物车中商品总价钱 public double getTotalPrice() { return totalPrice; } // 获取购物车中的商品信息 public Map<String, Integer> getCartItems() { return cartItems; } }的测试代码

Map<String, Integer> items = cart.getCartItems(); for (String productId : items.keySet()) { System.out.println("商品编号：" + productId + "，数量：" + items.get(productId)); } // 更新购物车中...

if(cursor.moveToFirst()) { @SuppressLint("Range") String productName = cursor.getString(cursor.getColumnIndex(DBHelper.COLUMN_NAME)); @SuppressLint("Range") float productPrice = cursor.getFloat(cursor.getColumnIndex(DBHelper.COLUMN_PRICE)); int productQuantity = 1; ShoppingCartItem itemg = new ShoppingCartItem(productName, productPrice, productQuantity); ShoppingCart.getInstance().addItem(itemg); Toast.makeText(getApplicationContext(), "商品添加成功！", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(getApplicationContext(), "该商品不存在！", Toast.LENGTH_SHORT).show(); } cursor.close(); }详细解释每一行代码

: 将购物车商品添加到购物车实例中，ShoppingCart.getInstance()获取购物车实例，.addItem(itemg)方法将商品添加到购物车中。 7. Toast.makeText(getApplicationContext(), "商品添加成功！", Toast.LENGTH_...

List<OrderDetail> orderDetailList = new ArrayList<>(); for (ShoppingCart cart : shoppingCartList) { OrderDetail orderDetail = new OrderDetail(); BeanUtils.copyProperties(cart, orderDetail); orderDetail.setOrderId(order.getId()); orderDetailList.add(orderDetail);

这段代码是将购物车列表中的每个商品转换为订单详情并添加到订单详情列表中。具体来说，代码使用了一个 for 循环遍历购物车列表中的每个商品，然后使用 BeanUtils 工具类将购物车对象的属性值拷贝到订单详情对象中。...

import { mapState } from "vuex"; export default { name: 'ShoppingCart', data() { return { selectNumber: 0,//选择的数目 total: 0,//总价 selectflower: []//选择的花 } }, computed: { ...mapState({ cart: (state) => state.cart, }), }, methods: { selectChange(selection) {//选择商品 this.selectflower = selection; this.selectNumber = selection.length; let total = 0; selection.forEach(item => { //总价=总价+商品数商品价格 total += item.number item.price }); this.total = total; }, deleteflower(flower) {//删除花 this.$store.commit('DELETE', flower); }, detail(flower) {//查看花的详情 this.$router.push('/flower') //页面路由跳转 this.$store.commit('DETAIL', flower)//同步操作，数据提交至 mutations ，this.$store.commit('方法名',值)【存储】 }, addNumber(flower) {//增加花的数量 this.$store.commit('ADD', flower) }, subNumber(flower) {//算花的总和 if (flower.number == 1) { this.deleteflower(flower); } else { this.$store.commit('SUB', flower) } }, pay() {//支付商品 this.$store.commit('PAY', this.selectflower) this.$message({ type: 'success', message: '结算成功！共支付' + this.total + '元' }) } } }

这段代码是一个 Vue 组件，主要是用于购物车页面的展示和操作。代码中使用了 Vuex 状态管理库来管理购物车数据，其中 mapState 函数用于将 store 中的状态映射为组件的计算属性。在 data 中定义了一些组件内部的...

白色大气风格的旅游酒店企业网站模板.zip

相关推荐

jquery.shoppingcart:使用本地存储的简单购物车jQuery插件

ShoppingCart.zip

shoppingcart.jsp

BigDecimal totalAmount = BigDecimal.valueOf(0); for (ShoppingCart shoppingCart : shoppingCarts) { BigDecimal amount = shoppingCart.getAmount(); Integer number = shoppingCart.getNumber(); totalAmount += amount * number; }

<jsp:useBean id="cart" scope="session" class="model.ShoppingCart"></jsp:useBean>

JSTL流程控制：<c:choose>实例解析

EL语言与JSTL标签库：<fmt:setLocale>解析

List<OrderDetail> orderDetailList = new ArrayList<>(); for (ShoppingCart cart : shoppingCartList) { OrderDetail orderDetail = new OrderDetail(); BeanUtils.copyProperties(cart, orderDetail); orderDetail.setOrderId(order.getId()); orderDetailList.add(orderDetail);

白色大气风格的旅游酒店企业网站模板.zip

最新推荐

白色大气风格的旅游酒店企业网站模板.zip

RStudio中集成Connections包以优化数据库连接管理

管理建模和仿真的文件

Keil uVision5全面精通指南

flink提交给yarn19个全量同步MYsqlCDC的作业，flink的配置参数怎样设置

PHP博客旅游的探索之旅

"互动学习：行动中的多样性与论文攻读经历"

【单片机编程实战】：掌握流水灯与音乐盒同步控制的高级技巧

java 号码后四位用‘xxxx’脱敏

Arachne:实现UDP RIPv2协议的Java路由库